Picture your twenty-first birthday. Did you have a party? If so, do you remember who was there? Now step back: how clear are those memories? Should we trust them to be accurate, or is there a chance that you're remembering incorrectly? And where have the many details you can no longer recall gone? Are they hidden somewhere in your brain, or are they gone forever?

Such questions have fascinated scientists for hundreds of years, and, as Alison Winter shows in Memory: Fragments of a Modern History, the answers have changed dramatically in just the past century. Tracing the cultural and scientific history of our understanding of memory, Winter explores early metaphors that likened memory to a filing cabinet; later, she shows, that cabinet was replaced by the image of a reel of film, ever available for playback. That model, too, was eventually superseded, replaced by the current understanding of memory as the result of an extremely complicated, brain-wide web of cells and systems that together assemble our pasts. Winter introduces us to innovative scientists and sensationalistic seekers, and, drawing on evidence ranging from scientific papers to diaries to movies, explores the way that new understandings from the laboratory have seeped out into psychiatrists' offices, courtrooms, and the culture at large. Along the way, she investigates the sensational battles over the validity of repressed memories that raged through the 1980s and shows us how changes in technology-such as the emergence of recording devices and computers-have again and again altered the way we conceptualize, and even try to study, the ways we remember.

Packed with fascinating details and curious episodes from the convoluted history of memory science, Memory is a book you'll remember long after you close its cover.